1. Field of the Invention
The present invention relates to a gas absorption device arranged in a liquid container for storing a liquid to be fed to a liquid consumption apparatus, a method of manufacturing the same, and a liquid container having the built-in gas absorption device. The gas absorption device has a function for absorbing gas dissolved in a liquid in the liquid container.
2. Description of the Related Art
As a representative example of a conventional liquid consumption apparatus, there is a liquid ejecting apparatus for ejecting liquid drops from an ejecting head. As a representative example of the liquid ejecting apparatus, there is an ink jet recording apparatus having an ink jet recording head for image forming. The ink jet recording apparatus makes comparatively little noise during printing and can form small dots of high density, so that in recent years, it is used for many types of print including color print.
As a liquid feed method for a liquid consumption apparatus represented by an ink jet recording apparatus, there is a method for feeding a liquid to a liquid consumption apparatus from a liquid container storing the liquid. Furthermore, in the liquid feed method by the liquid container, to enable a user to simply exchange the liquid container at the point of time when the liquid in the liquid container is consumed, the liquid container is generally structured as a cartridge which is removably mounted on the liquid consumption apparatus.
Generally, the ink jet recording apparatus has a carriage provided with a recording head for ejecting ink drops, which moves back and forth along the recording face of a recording medium. As a method of feeding an ink from an ink cartridge to a recording head, there is a method that the ink cartridge is mounted on the carriage and ink is fed from the ink cartridge moving back and forth together with the recording head to the recording head. Further, as another method, there is a method that the ink cartridge is mounted in the case of the apparatus body and ink is fed from the ink cartridge to the recording head via an ink flow path made of a flexible tube.
Meanwhile, when the ink cartridge is filled with ink and then is left for many hours as it is, N2 may be generated due to a chemical change of the dye in the ink. Further, when the barrier resistance of the ink container constituting the cartridge is low, there is a possibility that N2 and/or O2 may permeate from the outside through the container wall into the inside so as to be mixed in ink.
And, when printing is executed in the state that N2 and/or O2 is much dissolved in ink in the ink cartridge, bubbles may be produced in ink due to pressure changes during ejection of ink. When bubbles are produced in ink like this, defective ejection is caused due to sealing of the ink flow path by bubbles and there is a possibility of deterioration in the printing quality.
To solve the aforementioned problems, in Japanese Patent Laid-Open Publication 1-208145, an ink container for ink jet recording having a vacuum portion covered with a partition member which is insoluble in the ink components and permeable to gas is proposed.
Further, in Japanese Patent Laid-Open Publication 9-327930, an ink container for an ink jet recording apparatus in which by a film permeable to gas arranged in the ink container, the inside of the ink container is divided into an ink containing chamber and a negative pressure gas take-in chamber for taking gas into ink is proposed.
However, in the ink container having the vacuum portion covered with a partition member proposed in Japanese Patent Laid-Open Publication 1-208145, the examination of the decompressed status in the vacuum portion is very difficult and a problem arises that whether a predetermined decompressed status is ensured at the time of manufacture or not cannot be confirmed.
Further, also in the ink container which is internally divided into the ink containing chamber and the gas take-in chamber by the permeable film proposed by Japanese Patent Laid-Open Publication 9-327930, similarly, the examination of the decompressed status in the gas take-in chamber is very difficult and a problem arises that whether a predetermined decompressed status is ensured at the time of manufacture or not cannot be confirmed.
Further, in the ink container having the vacuum portion covered with the partition member proposed in Japanese Patent Laid-Open Publication 1-208145, the concerned vacuum portion is not fixed to the ink container, so that when the ink container is given a shock such as vibration or falling, there is a possibility that the vacuum portion covered with the partition member may collide with and damage the inner surface of the ink container. Further, if an ink pack formed by a flexible bag is used, when the vacuum portion covered with the partition member is located at the end position away from the ink feed port of the ink pack, the ink pack is hardly crushed, thus a problem arises that the residual amount of ink is increased.
Further, in the ink container which is internally divided into the ink containing chamber and the gas take-in chamber by the permeable film proposed by Japanese Patent Laid-Open Publication 9-327930, since the decompressed space is formed using the outer film forming the ink container, a problem arises that the manufacture of an ink container and the operation of filling ink are very complicated.
Further, in Japanese Patent Laid-Open Publication 9-327930, an example that the decompressed space is formed only by a film permeable to gas separately from the outer film is also described. In this example, the bag of a permeable film covered with a decompressed space forming member is arranged at a position away from the ink feed port of the ink container, so that a problem arises that the ink pack is hardly crushed and the residual amount of ink is increased.